Riveting tool



Oct. 8, 1940.

S. B. DAVITOW RIVETING TOOL Filed July 27. 1938 INVENTOR SERGO B.DAVITOW. BY

ATTORNEY Patented Oct. 8, 1940 UNITED STATES RIVETING TOOL Serge B.Davitow, St. Albans, N. Y.

Application July 27, 1938, Serial No. 221,636

7 Claims.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370O. G. 757) of the barrel ll between a pair of upstanding This inventionrelates to a riveting tool and has Jfor an object to provide an easilyoperable tool for expanding a hollow rivet which has been placed throughtwo pieces of sheet material to secure the pieces of sheet materialtogether. It .is especially intended for use in cases where the sheetmaterial is metal and where the ends of the sheet material are notsuiiiciently accessible to allow the tool to overlap one of the ends.

A further object of this invention is to provide a riveting tool whichis hand operated and in which the operating handles are mounted as apair of levers pivoted one upon the other and adapted to be closedtoward one another during the riveting operation in the same manner thatthe handles of a pair of pincers are operated.

A further object of this invention is to provide a hand operatedriveting tool which can exert a powerful leverage to positively operatethe riveting mechanism of the tool.

With the foregoing and other objects in view, the invention consists inthe construction, combination and arrangement of parts hereinafterdescribed and illustrated in the drawing, in which, 7

Fig. l is a partly sectional and partly elevational view of the rivetingtool of this invention in closed position.

Fig. 2 is a fragmentary elevational view of the riveting tool in openposition.

Fig. .3 is a sectional view, similar to Fig. 2.

Fig. 4 is a sectional view on line 4-4 of Fig. 2.

'Fig. 5 is an end View of the riveting end of the tool, and

Fig. 6 is a sectional view on line 66 of Fig. 2.

There is shown at ID the riveting tool of this invention which includesa hollow handle lever II to which is pivoted at l2 another hollow handlelever I3. Stopper members It and I5, welded or otherwise secured to thelevers II and I3, limit the approach of the levers H and I3 to eachother about their pivot l2. The end of the lever H is ofiset as at 16and carries thereon a squared barrel ll which .is in axial alignmentwith the lever l3 when the lever 13 is closed against lever H. Thisbarrel terminates in a .nozzle is. Slidable within the squared barrel Il is a squared piston 48 which may be pulled through the open end IQ ofthe barrel H by means of a pair of link arms 20 which are pivoted at 21to the handle lever l3, as shown.

The other end of the squared piston 18 is bifurcated as shown at 22,permitting a mandrel puller bottom jaw .23 to be secured between thebifurcations as at 2 4. Pivoted above the jaw 23, at 2:5, is a mandrelgrip lever 2:6 provided with a cammed upper surface 27. The free end ofthe grip lever 28 presses against a compression spring 28 sunk within awell 29 formed within the squared piston 18. Journaled above the rearend ears 3% is .a lever roller 31, the roller or abutment 3i beingmounted over the end of a longituclinal slot 32 along the center of thetop of the squared barrel l I through which the cammed surface Z 'l ofthe grip lever 26 may extend. A mandrel 33 consisting of a rod having anenlarged head 34 is adapted to be placed through the hollow rivet 35 andthrough the nozzle l8 to a position between the serrations 36 on thebottom jaw 23 and the serrations 3'! on the grip lever 26.

In operation, the sheets of material 38 and 39 being riveted togetherhave the hollow rivet 35 placed therethrough in appropriate aperturespreviously formed therein. Mandrel 33 is then placed through the hollowrivet 35 until the head 34 abuts the end. of the rivet. the mandrel 33is extended through the .nozzle !8' into position between the serrations36 and 3l-on the jaw 23 and lever '26 while the handles I i and 13 arespread apart,--thereby permitting the spring 28 to raise the lever 26about its eccentric pivot 25, spacing the serrations suflicientlydistant to permit the mandrel to enter therebetween. Movement of thehandles II and I3 toward each other through links 2!) draws the pistonit partly through the opening 19 and causes the vcammed surface 21 oflever to pass under the lever roller 31 and pivot the serrations .31 totightly grip the mandrel 33 against the serrations 36 of the bottom jaw23. Further approach of the handle 13 to the handle H pulls the completeassembly rearwardly, causing the head 34 of the mandrel 33 to approachthe nozzle t8 and thus expand the rivet to the riveted position .shownat til, the stops l4 and i5 limiting the approach of the levers H and [3to the proper distance so that the movement of the mandrel head 34 isstopped when the rivet 35 has been properly expanded to the position Ml.Moving the handle levers I! and I3 apart reverses the operation inpushing the mandrel 33 partly out of the now emanded rivet 40, allowingthe mandrel 33 to be withdrawn and replaced in a new rivet for furtheroperation. Alternately, the mandrel .33 may be .an inexpensive nail ofsuitable size, which may be discarded and replaced at each rivetingoperation.

It will be noted from Fig. 1 of the drawing that when the handles II andI3 approach their closed position, that because of the leverage, thepull exerted on the mandrel 33 is very great. The purpose of thisarrangement is not only to provide the required pulling force on themandrel 33 to effect the desired expanding of the rivet, but also, ifdesired, when 'using a mandrel "having a tapered head shown in thedrawing to pull the head *Mx-of-the mandrel entirely through the rivetopening. The mandrel head which is In this position slightly deformed inthis operation serves to expand the shank of the rivet sufiiciently toform a secure fastening.

Other modifications and changes in the proportions and arrangements ofthe parts may be made by those skilled in the art without departing fromthe nature of the invention, within the scope of what is hereinafterclaimed.

The invention described herein may be manufactured and used'by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

Having thus set forth and disclosed the nature of this invention, whatis claimed is:

1. A riveting tool for pulling a mandrel having a body portion adaptedto pass through a hollow rivet having a head at one end and beingheadless at the other end, which headless end is to be expanded into anout-turned flange by a head portion on the mandrel larger than thehollow rivet and being adapted to expand the headless end portion of therivet when the mandrel is pulled into the rivet while maintaining thehead of the rivet stationary relative to the tool, said tool comprisingmeans for engaging the body portion of the mandrel for pulling the sameinto the rivet comprising a barrel, a piston movable Within said barrel,a serrated jaw fixed in said piston, a cammed serrated jaw eccentricallypivoted in said piston, means for pulling said piston out of said barreland other means for simultaneously camming said cammed jaw intoengagement with said mandrel body to thereby expand the rivet.

2. A riveting tool for pulling a mandrel having a body portion adaptedto pass through a hollow rivet having a head at one end and beingheadless at the other end, which headless end is to be expanded into anout-turned flange by a head portion on the mandrel larger than thehollow rivet and being adapted to expand the headless end portion of therivet when the mandrel is pulled into the rivet while maintaining thehead of the rivet stationary relative to the tool, said tool comprisingmeans for engaging the body portion of the mandrel for pulling the sameinto the rivet comprising a barrel, a piston movable within said barrel,a serrated jaw fixed in said piston, a cammed serrated jaw eccentricallypivoted in said piston, means for pulling said piston out of said barreland other means for simultaneously camming said cammed jaw intoengagement with said mandrel body to thereby expand the rivet, said.pulling means comprising a handle lever on which said barrel is mounted,a second handle lever pivoted to said first handle lever, and meanslinking said piston to said second handle lever.

3. A riveting tool for pulling a mandrel having a body portion adaptedto pass through a hollow rivet having a head at one end and beingheadless at the other end, which headless end is to be expanded into anout-turned flange by a head portion on the mandrel larger than thehollow rivet and being adapted to expand the headless end portion of therivet when the mandrel is pulled into the rivet while maintaining thehead of the rivet stationary relative to the tool, said tool comprisingmeans for engaging the body portion of the mandrel for pulling the sameinto the rivet comprising a barrel, a piston movable within said barrel,a serrated jaw fixed in said piston, a cammed serrated jaw eccentricallypivoted in said piston, means for pulling said piston out of said barreland other means for simultaneously camming said cammed jaw intoengagement with said mandrel body to thereby expand the rivet, saidpulling means comprising a handle lever on which said barrel is mounted,a second handle lever pivoted to said first handle lever, means linkingsaid piston to said second handle lever, and a cam cooperating rollerjournaled on said barrel in the path of said cammed lever adapted topress and hold said cammed lever in mandrel gripping and holdingposition as the piston is drawn along under the roller.

4. In a device for aflixing a tubular rivet by drawing a mandrel throughit, said mandrel being formed as a rod with an enlarged head adapted toupset a headless end of a rivet to afilx it, a casing, an axiallysliding member supported by said casing and having a fixed clamping walland a clamping part, means operating on sliding movement of said memberto cause said part to engage said mandrel and to clamp the mandrelagainst said wall, means to disengage said mandrel to release the same,a handle fixed to said casing, a second handle mounted in pivotalrelation to the first named handle, and a connection between said secondnamed handle and said member for sliding said member.

5. In a device for affixing a tubular rivet by drawing a mandrel throughit, said mandrel having an enlarged head adapted to upset the headlessend of the rivet to affix it, an axially reciprocating member havingmandrel clamping jaws, means to cause the jaws to grip the mandrelduring the sliding movement of the member in one direction and to holdthe mandrel gripped while it is moved into clamping affixing engagementwith the rivet and on movement in the other direction to maintain thegripipng engagement with the mandrel, and means operating after apredetermined movement of said member in said other direction to releasesaid mandrel for withdrawal from the device.

6. In a device for afiixing a tubular rivet by drawing a mandrel throughit, said mandrel having an enlarged head adapted to upset the headlessend of the rivet to alflx it, an axially reciprocating member havingmandrel clamping jaws, means to cause the jaws to grip the mandrelduring the sliding movement of the member in one direction and to holdthe mandrel gripped while it is moved into clamping aflixing engagementwith the rivet and on movement in the other direction to maintain thegripping engagement with the mandrel, and resilient means operatingafter a predetermined movement of said member in said other direction torelease said mandrel for withdrawal from the device.

'7. In a device for aflixing a tubular rivet by drawing a mandrelthrough it, said mandrel having an enlarged head adapted to upset aheadless end of a rivet to affix it, a casing, an axially sliding memberin said casing having mandrel clamping jaws, one of which is formed witha cam surface, an abutment on the casing in contact with which saidsurface moves on motion of said member in one direction whereby said jawis moved to clamp the mandrel and maintain it clamped during continuedmovement in said direction and means for releasing said jaw on movementof said member in the opposite direction.

SERGO B. DAVITOW.

